Process of extracting fat from wool



(No Model.) 4

7 P. G. McILHINEY.

PROGESS 0P BXTRAUTING FAT FROM WOOL. No; 551,396. Patented'Dec. 17,1895.

W I 17685 [21 were for,

UNITED" STATES PATENT OFFICE.

PARKER O. MGILHINEY, OF JERSEY CITY, NEIV JERSEY.

PROCESS OF EXTRACTI NG FAT FROM WOOL.

SPECIFICATION forming part of Letters Patent No. 551,396, dated December17, 1895.

Application filed A g t 10, 1894. Renewed Apri123, 1895. Serial No.546,925. (No specimens.)

T0 ail whom it may concern:

Be it known that I, PARKER O. MOILHINEY, a citizen of the United Statesof America, residing at .Iersey City, county of Hudson, State of NewJersey, have invented certain new and useful Improvements in Processesof Cleansing and Removing Fat or Grease from lVool, of which thefollowing is a specification.

lleretofore wool has been cleansed by washing it in aqueous solutions ofsoap or of alkalies, by the use of volatile solvents, as benzine,benzol, toluol, naphtha, carbon disulphide, carbon tetrachloride, &o;,the solvent being afterward separated from the/fat 01f grease bydistillation, or by the use of nonvolatile solventsfas parafIine-oil,the fat or grease being afterward partially separated from the solventby cooling and subsidence.

The use of volatile solvents-i e., solvents boiling below 150centigradeis attended with much inconvenience on account of thedifficulty of preventing; loss of solvent by evaporation, and with mostsolvents the great danger of fire. be conducted in closed vessels, whichis inconvenient.

In the case of non-volatile solvents, as parafline-oil, it is extremelydifficult to remove from the wool the last traces of solvent, andmoreover the solvent cannot be economically recovered from its mixturewith the grease or fat. The grease or fat obtained by this process isnot pure, being contaminated with solvent.

My improvement consists in using as a solvent for washingthe woola'liquid whose boiling-point is sufficiently high to allow of its beingused with safety in open vessels, and afterward recoveringthe solventand sepa- The operation must therefore ture low enough not to injurethegrease.

I find that if the wool is washed with a solvent maintained at too higha temperature it is inj ured thereby, and I do not in carrying out myprocess consider it advisable to use a'temperature much higher than 50centigrade.

lVhile the wool is being washed in the solv ent it should be slightlyagitated to allow the dirt and potash salts which are insoluble in thesolvent to separate from the wool and fall to the bottom of the vessel,which should be provided with a perforated false bottom. I find thatthis agitation is best accomplished by using for washing the wool withsolvent an apparatus similar to the ones at present in use for washingwool with aqu eous solution of soap and alkalies, in which the wool ismoved gently through the liquid by rakes and fingers.

The insoluble material found beneath the false bottom of the washingapparatus, and also that obtained by filtering or settling the mixtureof fat or grease with solvent, contains most of the potash originallycontained in the wool. After removing the solvent from it bypressing,distillation, or in any suitable manner it is incinerated to destroyorganic matter and liXivia-ted with water to extract the potash. Thepotash is then recovered from the water solution by evaporation.

After the wool has been washed in the solvent it is washed with waterand squeezed between rollers, pressed, rotated in a centrifugal machinewith perforated sides, or pressed in any suitable way to remove as faras possiblethe solvent remaining in the wool. I

prefer to accomplish this result by pressing the wool between hollowrolls which have perforated surfaces to facilitate the removal of theliquid from the wool and to pass the wool several times into water andbetween pairs of such rolls, as Ifind thatin subjecting wool whichcontains solvent and water several times to the action of such pressurethe solvent is almost entirely removed in an emulsified state. The waterused for this washing is after use allowed to run into a settlingtankwhere the emulsified solvent separates from the water and is returned tothe washing apparatus. After this washing the wool is quite clean exceptfor the presence of a very small quantity of solvent which evaporates inthe course of a few hours.

If it is desired the wool may be given a final rinsing in a weak soapbath to improve its appearance.

In the accompanying drawings, Figure lis a plan of a form of apparatusadapted to carry out my process, and Fig. 2 is a sectional elevation ofthe same.

There is a tank A which is provided with a perforated false bottom a.Into this tank solvent is allowed to run after being heated to theproper temperature either in the re ceiver I or in any other suitablevessel. The wool is then thrown into this tank and allowed to soak for atime, when the grease is dissolved by the solvent, and the dirt andpotash salts which the grease fastened to the fiber being now liberatedfall to the bottom of the vessel beneath the false bottom, whichprevents the wool from again coming in contact with the dirt. While thewool is soaking in the solvent it is gently agitated, and after it hasbeen sufficiently treated is thrown onto an apron N, which carries it toa pair of squeeze-rolls D. The pressure on these rolls may be regulatedby any suitable arrangement. The rolls press most of the solvent out ofthe wool and another apron N throws it into a tank 13, which is similarto A but which need not be provided with a false bottom. This tank Bcontains warm water. The wool is gently agitated in this water for ashort time to remove any dirt which the solvvent in tank A had failed toremove and is then thrown onto the apron 0 leading to the rolls E. Theserolls squeeze out from the wool an emulsion of solvent and water, whichfalls into the tank 0, and the wool is carried off in a clean state byanother apron 0. Motion is imparted to the two rolls and to the movableaprons by the drums TV. The wool may still contain traces of solvent,but this evaporates in a short time, the drying being hastened, ifnecessary, by heat, or by placing the wool in a closed vessel andexhausting the air therefrom, or in any other suitable manner. Theemulsion of solvent and water separates by gravity into its twoconstituents and the two are drawn off separately by suitable cocks,(shown in the drawings,) the solvent so obtained being returned to tankA.

When the solvent in tank A contains sufficient grease, the pump Pconveys it to the filter F. This is a tank which contains a screencovered with cloth to act as a filter. The solvent containing the greasein solution is in this way separated from the dirt and potash saltswhich collect above the screen and are removed at suitable intervals.

From the filter F the filtered liquid is conveyed by the pipe f,provided with a stopcock, to the still G, which is provided with athermometer and a perforated steam-coil g", as shown in the drawings,and is also heated by the fire M. In this still the liquid is heated toa temperature of about 200 centigrade and steam admitted to theperforated coil g. The heat and free steam volatilize the solvent which,together with the steam, passes over into the condenser H. In thiscondenser the vapors are cooled and thereby liquefied and flow into thereceiver 1, where the water and solvent separate by gravity and thewater is drawn oh? by the cock 2', shown in the bottom of the receiver.The receiver I is provided with a close steam-coil it, which is intendedto heat the solvent to the proper temperature before allowing it to runby the pipe 1', shown in the side of the receiver, into the tank A to beagain used in cleaning fresh material. After all the solvent has beenvolatilized in the still G nothing remains but the fat or grease. Theheating and admission of steam to the perforated coil are now suspendedand the grease is drawn off by the cock g, shown in the lower part ofthe side of the still.

I do not confine myself to the use of this form of apparatus, but anyother suitable apparatus may be used. For example, the wool .while it isimmersed in the solvent in the I claim, and desire to secure by LettersPatent, is:-

1. The process of cleansing and extracting fat or grease from wool whichconsists in washing the wool with a solvent which boils sub stantiallybetween 170 and 250 centigrade, the solvent being maintained at atemperature which will not injure the wool, and afterward recovering thesolvent by distillation.

2. The process of cleansing and extracting fat or grease from wool whichconsists in washing the wool with a solvent which boils sub- IIOstantially between 17 0 and 250 Centigrade, the solvent being maintainedat a temperature which "will not in jute the W001, separatingthe W001from the solvent, heating the solvent containing the fat or grease insolution in a still provided with a condenser, passing steam through theliquid to assist in V012L- tilizing the solvent, and condensing thesolvent for use in cleansing fresh material.

PARKER- O. MCILHINEY.

\Vitnesses GEORGE G. TENNANT, ROBERT CAREY.

